Why isn't ethics more integrated into current AI systems?
This is necessarily a high-level answer, and highly speculative, but I've been thinking on this question, and here are my thoughts:


Implementing ethical algorithms requires a mathematical basis for philosophy because computers are difference engines


After Russell &amp; Whitehead's famous failure, and Gödel's incompleteness theorem, this would seem to be problematic. 


AI is a highly applied field, especially today per continuing validation of deep learning, and no company wants to go near the issue of ethics unless they are forced to


Thus, you see it in self-driving cars because the engineers have no choice but to grapple with the problem.  By contrast, I don't think you'll see many algorithmic stock trading firms, where the business is Pareto efficiency, worrying about the ethics or social impacts of financial speculation. (The solution to "flash crashes" seems to have been rules for temporary suspension of trading, instead of addressing the social value of high-frequency algorithmic trading.) A more obvious example is social media companies ignoring the extreme amounts of information abuse (disinformation and misinformation) being posted on their sites, pleading ignorance, which is highly suspect in that the activity generated by information abuse positively affects their bottom-lines.


Applied fields tend to be predominantly driven by profit


The primary directive of corporations is to return a profit to investors.  It's not uncommon for corporations to break the law when the fines and penalties are expected to be less than the profit made by illegal activity.  (There is the concept of ethics in business, but the culture in general seems to judge people and companies based on how much money they make, regardless of the means.)


Implementation of machine ethics is being explored in areas where they are necessary to sell the product, but elsewhere, it's still largely hypothetical


If superintelligences evolve and wipe out humanity (as some very smart people with superior mathematics skills are warning us about,) my feeling is that it will be a function of nature, where unrestricted evolution of these algorithms is due to economic drivers which focus on hyper-partisan automata in industries like financial speculation and autonomous warfare.  Essentially, chasing profits at all costs, regardless of the impacts.